Careful, there are a lot of dodgy USB "chargers" out there these days. Typically they'll have poor regulation that might be ok for most phone's charging circuits, but not so good for powering ics directly.

In the simplest form, it can be a rc network. In a more reasonablly engineered form, it could contain an isolated switching mode power supply, with good common mode filtering and power factor correction, and low idle power -> you may find a mcu far more powerful than you arduino reside in one of them.

The cheapos you get off ebay probably are a lot closer to the dangerously simple types.

Why settle for a ford mondeo when for an extra few bucks you could buy a ford GT ..

is it not better to "have" than have not?

The origional request seems to read "Probably atleast 100ma". For only $1 shipped it would be worth a try. Bigger and more expensive may not be better. Why buy a ford GT when all the kids won't fit in when going to the store?

Google forum search: Use Google Search box in upper right side of this page. Why I like my 2005 Rio Yellow Honda S2000 https://www.youtube.com/watch?v=pWjMvrkUqX0

That's a nice article -- the one at Ken Shirriff's blog. I'm far from an Apple fanboi, but they do, in most cases, build very good hardware. I'm now curious what the guts of my LG charger look like. It sure isn't a $30 item.

... it is poor civic hygiene to install technologies that could somedayfacilitate a police state. -- Bruce Schneier

The requirement was definetly a minimum, more the merrier, this is for a design for somethi that is going to be behind regular house outlets and switches(probably in the same box, so im trying to keep it cool and small as possible, basically going to be powering an attiny84/85, relays, leds, perhaps some other comm peripheralsso while quality isn't the most important, reliability definetly is, something that could be expected to last perhaps atleast 3 years by itself in a closed enviroment, without gtting hot or posing a fire hazard lol